0000000000140217

AUTHOR

T. Tsuboyama

showing 5 related works from this author

Search for an Invisibly Decaying Z′ Boson at Belle II in e+e−→μ+μ−(e±μ∓) Plus Missing Energy Final States

2020

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z′. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z′ in the process e+e-→μ+μ-Z′ and of a lepton-flavor-violating Z′ in e+e-→e±μZ′. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an Lμ-Lτ theory, into upper limits on the Z′ coupling constant at the level of 5×10-2-1 for MZ′≤6 GeV/c2.

PhysicsCoupling constantParticle physicsMissing energyPhysics beyond the Standard ModelGeneral Physics and Astronomy01 natural scienceslaw.inventionlaw0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsColliderBosonPhysical Review Letters
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The Belle II vertex detector integration

2019

Belle II DEPFET, PXD, and SVD Collaborations: et al.

Nuclear and High Energy PhysicsPhysics::Instrumentation and DetectorsSilicon sensorPhase (waves)Computer Science::Computational Geometry7. Clean energy01 natural scienceslaw.inventionNuclear physicsBelle II; Data acquisition; Pixel detector; Silicon sensor; Strip detector; Vertex detector; Nuclear and High Energy Physics; InstrumentationData acquisitionlaw0103 physical sciencesVertex detectorBelle IIStrip detectorColliderInstrumentationNuclear and High Energy PhysicPhysicsInterconnectionPixel010308 nuclear & particles physicsDetectorBelle II; data acquisition; pixel detector; silicon sensor; strip detector; vertex detectorData acquisitionPixel detectorUpgradeHigh Energy Physics::ExperimentFocus (optics)Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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Precise Measurement of the D0 and D+ Lifetimes at Belle II

2021

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72  fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst)  fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst)  fs, are the most precise to date and are consistent with previous determinations.

PhysicsParticle physics010308 nuclear & particles physicslaw0103 physical sciencesGeneral Physics and AstronomyResonance010306 general physicsCollider01 natural scienceslaw.inventionLuminosityPhysical Review Letters
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First Observation ofCPViolation inB¯0→DCP(*)h0Decays by a Combined Time-Dependent Analysis ofBABARand Belle Data

2015

We report a measurement of the time-dependent CP asymmetry of B0->D(*)CP h0 decays, where the light neutral hadron h0 is a pi0, eta or omega meson, and the neutral D meson is reconstructed in the CP eigenstates K+ K-, K0S pi0 or K0S omega. The measurement is performed combining the final data samples collected at the Y(4S) resonance by the BaBar and Belle experiments at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain ( 471 +/- 3 ) x 10^6 BB pairs recorded by the BaBar detector and ( 772 +/- 11 ) x 10^6, BB pairs recorded by the Belle detector. We measure the CP asymmetry parameters -eta_f S = +0.66 +/- 0.10 (stat.) +/- 0.06 (syst.) an…

PhysicsParticle physicsMeson010308 nuclear & particles physicsmedia_common.quotation_subjectHadronGeneral Physics and Astronomy01 natural sciencesOmegaAsymmetryB-factoryNuclear physicsKEKB0103 physical sciencesD mesonCP violation010306 general physicsmedia_commonPhysical Review Letters
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The Belle II Physics Book

2019

cd. autorów: L. Cao48,‡, G. Caria145,‡, G. Casarosa57,‡, C. Cecchi56,‡,D. Cˇ ervenkov10,‡,M.-C. Chang22,‡, P. Chang92,‡, R. Cheaib146,‡, V. Chekelian83,‡, Y. Chen154,‡, B. G. Cheon28,‡, K. Chilikin77,‡, K. Cho70,‡, J. Choi14,‡, S.-K. Choi27,‡, S. Choudhury35,‡, D. Cinabro170,‡, L. M. Cremaldi146,‡, D. Cuesta47,‡, S. Cunliffe16,‡, N. Dash33,‡, E. de la Cruz Burelo9,‡, E. de Lucia52,‡, G. De Nardo54,‡, †Editor. ‡Belle II Collaborator. §Theory or external contributing author. M. De Nuccio16,‡, G. De Pietro59,‡, A. De Yta Hernandez9,‡, B. Deschamps129,‡, M. Destefanis60,‡, S. Dey116,‡, F.Di Capua54,‡, S.Di Carlo75,‡, J. Dingfelder129,‡, Z. Doležal10,‡, I. Domínguez Jiménez125,‡, T.V. Dong30,26,…

B: semileptonic decayPhysics beyond the Standard ModelHadronelectroproduction [charmonium]General Physics and AstronomyComputingMilieux_LEGALASPECTSOFCOMPUTINGB: radiative decayannihilation [electron positron]7. Clean energy01 natural sciencescharmonium: electroproductionB physicsHigh Energy Physics - Experimentlaw.inventionHigh Energy Physics - Experiment (hep-ex)High Energy Physics - Phenomenology (hep-ph)Z'law[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Charm (quantum number)dark sector searchesPhysicslifetimeradiative decay [B]doublet [Higgs particle]new physicsPhysicsHigh Energy Physics - Lattice (hep-lat)ddc:530Electroweak interactionlepton: flavor: violationhep-phParticle Physics - LatticeMonte Carlo [numerical calculations]electron positron: colliding beamsQuarkoniumasymmetry: CPquarkonium physicselectroweak interaction: penguinHigh Energy Physics - PhenomenologyImproved performancecolliding beams [electron positron]CP violationinterfaceelectroproduction [quarkonium]electroweak precision measurementsnumerical calculations: Monte CarlophysicsParticle Physics - ExperimentperformanceParticle physicsflavor: violation [lepton]reviewhep-latFOS: Physical sciencesBELLEHigh Energy Physics - Experiment; High Energy Physics - Experiment; High Energy Physics - Lattice; High Energy Physics - Phenomenologyelectron positron: annihilationquarkonium: electroproductionCP [asymmetry]E(6)Higgs particle: doubletmixing [D0 anti-D0]Theoretical physicsCP: violation: time dependenceHigh Energy Physics - LatticeKEK-B0103 physical sciencesquantum chromodynamicshidden sector [photon]ddc:530composite010306 general physicsColliderParticle Physics - PhenomenologyHigh Energy Physics - Experiment; High Energy Physics - Lattice; High Energy Physics - Phenomenologyphoton: hidden sectorhep-ex010308 nuclear & particles physics[PHYS.HLAT]Physics [physics]/High Energy Physics - Lattice [hep-lat]C50 Other topics in experimental particle physicsviolation: time dependence [CP]D0 anti-D0: mixingB2TiP530 PhysikExperimental physicsB: leptonic decayCKM matrix[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]penguin [electroweak interaction]leptonic decay [B]semileptonic decay [B]charmparticle identificationexperimental results
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